Carbonizing process



July 2O 1926.

C. HAYES CARBONIZING PROCES S Filed May 22,4 1926 Patented July 20,1926.

CHARLES HAYES, F PARIS, FRANCE.'

cmom'zme Pnocnss.

pplicationled May 22, 1926, Serial No. 110,948, and in Canada Hay 18,1925.

My invention relates to processes of carbonizing coal and has for itsobject to provide a simple, eiicient andinexpensive method by which coaland coal-like material con- 1 taining an excess of volatiles may be sofar freed from volatiles as. to leave a coke-like product high in fixedcarbon with only such proportion of volatiles as may be desired for thepurpose 4ofenabling it to be readily igl0 nited. l

` The value of coal for-use as fuel depends upon the proportionatecontent of ixed car bon. If not too high in volatiles it may be used asa steam coal or may be coked. But

there are large deposits of coal which is so high in volatiles as' to benon-coking and of little value as fuel.' This is particularly true ofthe coal classed as a lignite whichis not only high in volatiles butalsocarries a large percentage of water.

By my inventionthis non-coking coal and lignite may be, quickly and atlittle expense, freed from excess of volatiles and water so as to leavea product composed mainly of fixed carbon free from water and containingonly such slight percentage of volatiles as nay be desired to make theproduct easy to ignite. The product obtained by my method` iscoke-like.and is well adapted for use as 80 domestic fuel as well` as for use forany other .fuel purpose, and is particularly umform in quality whateverthe original material from which it is made. -The volatiles driven offare largely composed of conden- 85 sable vapors and the oils condensedfrom these vapors are of substantial value and the volatiles driven o"as fixed gas are of value for heating the digesters or for sale as gasfor heating and illuminating.

With the objects above indicated in view my invention consists on theprocess hereinafter described and claimed.

' Referring to the drawings Figure 1 is a vertical sectional view, part-5 ly diagrammatical, of a plant adapted to carry out my invention.

Figure 2 is a detail cross plan view of the piston of one of thedigesters Figure 3 is a detail plan and vertical sectional view showingthe construction oi' the digester bottom.

It should be understood' that the drawings are illustrative only and arenot to be taken These di esters are open at their upper ends and at teir lower ends rest upon suitable cross beams 3. Near their upper endsthe digesters are provided with openings 50 for the escape of gases fromthe digesters into chamber 1. At their lower ends these digesters areclosed by hinged bottoms 4 pref# erablyeach consistlng of a main ortion5 provided with interrupted` screwt reads 6 adapted to be engaged withcorresponding interrupted screw threads 7 in the lower en 70 of thedigester, the main portion 5 being adapted to rotate in a ring 8 whichis hinged to the digester, this construction being adapted to be readilylocked and released and when locked in closed lposition capable ofsupportingv heavy pressure.

In each digester is arranged a piston 10 carried by a rod 11 extendingthrough guide plate 12 into a cylinder 1 3 arranged above the to ofchamber 1 and carrying a iston 14. ater or oil supplied to cylin er 13by pump 16 serves to force the iston 10 downward or to withdraw it asesired.

Below the lower endsof the digesters 2 is a bin 20 the bottom 21 ofwhich is arranged at a distance from the lower end of the digester aboutequal to half the vertical height of the digester so that when thebottom of the digester is opened and the pistony l10 is operated to exel the lower portion of the charge this expe led portion belng a solidmass of coke-like material with its lower end resting on the bottom 21of the bin forms'a supporting column by which the less sohd upperportion of the 'charge will supported and prevented from dropping out ofthe di ester. When the bottom is again closed this less solid portion ofthe charge will be in the lower portion of the digester in osition to besubjected to the relatively hi her heat and to be formed into a solid coe-like mass. A door 22 at one side of the bin 2O permits the inishedfuel product to be removed.

About the wall of the bin is arranged a chamber or tank 23 to besupplied with water to be converted into steam by the heat of thematerial discharged from the digester. The mass of material may, ifdesired, be further cooled by water from a hose or by other means.

About the digesters 2 between them and the walls of chamber 1, arepreferably arran d baffle plates 25 and beneath these batlee plates areburners 26 preferably for burning fuel oil though the digester may, ofcourse, be heated by other means. The air necessary for combustion maybe supplied to these burners in any usual manner as by an air pipe 51surrounding oil supply pipe 52. Between the baffle plates is arranged acoil 27 which is supplied with steam from any convenient source the coil27 serving to superheat the steam so supplied. The upperend of the coil27 is connected with pipes 28 referably three for each digester, leadingthrough guide plate 12 downward nearly to the lower end of the digester,these ipes being erforated at intervals from t eir lower en s to a pointabout o posite the midlength of the digester. T e pistons 10 areprovided with suitable openings for these superheated steam pipes. Thethree superheated steam pipes for each digester are preferably equallyspaced apart and at points about) lnidway between the center of thedigester and its inner periphery.

Near the upper end of each digester is an inlet openin 30 to which leadsa pipe 31 from a supp y pipe 32 which leads from a conveyer 33, hereshown as a screw conveyer of ordinary construction, operated by a pulley34. This conveyer is adapted to receive coal or other material from abin 35 and discharge it into pipes 31 and so into the digesters.

The coal or other material is supplied to bin 35 from a preliminaryheater 36 arranged to be heated by Vburner 37 and having at its outerend a ho per 38 to which the coal is supplied pre erably broken so thatits particles will not be too large to pass through a quarter inchscreen. The air necessary for combustion may be supplied to theseburners in any usual manner as by an air inlet pi e 53 inclosing oilsupply pipe 54. This preliminary heater is arranged to be rotated, by amotor 39 so as to effect avitation sufficient to prevent the articles ocoal from sticking together an to ensure even heating.

From the upper part of chamber 1 a. pipe 40 leads to a chamber 41 inwhich by means of a rotary screw 42 driven by motor 43 any particles ofdust or other solid matter carried over from the digester will be thrownoutward against the walls of the chamber to collect at its bottom.

The gas and vapors pass from chamber 41 by pipe 45 for such separationof the vapors and recovery of condcusates therefrom and such use of thefixed gas as may be desired.

By compressing the coal while it is in relatively soft condition theformation of gas pockets is preventedv and the material is made denseand solid, the resulting fuel being more dense and solid than ordinarycoke and having a specific gravity about the same as that of the rawmaterial used. B reason of its density and relatively hig speciticgravity the finished product is adapted to be transported at lowerfreight rates than ordinary coke.

In carrying out the process the coal or lignite previously crushed isintroduced into the preheater 36 where it is subjected to a heat ofabout 400 degrees F., the preheater being agitated to ensure evenness ofheating. From the preh'e'ater 36 the heated coal is discharged into bin35 from which it is conve ed by conve er 33 to the up r end of thedigester whic is heated by Eiirners 26 arranged at its base so that itslower portion is more highly heated than its upper portion, thus forminga lower high heat zone and an upper less heated zone. When the digesteris filled with the preheated coal the plun er 10 is operated'to com ressthe charge o coal, the effect of this fiist comression being to forcethe particles of coal mto a com act mass free from any large air or gaspoc ets. The heat being greater towards the lower ends of the digesterthe coal in that portion of the-digester becomes quickly softened andthe coal in the upper portion becomes more or less softened. The plungeris then again operated compressing the softened coal into a compact massand leaving a considerable space above it. Additional coal is then fedinto the upper 'end of the digester until it is full, and the plunger isoperated to com ress this additional charge. The heat being continued,the coal in the lower portion of the digester becomes a relatively solidmass of coke-like material from which the volatiles have been mainlyeliminated leaving only suiicient volatiles to make the fuel productreadily ignitable.

As soon as the material in the lower portion of the digester issuiciently heated the lower end of the digester is opened by unlockingthe bottom 4 and permitting 1t to swin down and the plunger is againforced own to force the contents of the digester downward until thelower end of the expelled mass strikes the bottom 21 of the bin 20 andits further movement is revented, the digester being thus left filed forabout half lts length, the partly treated material previously in theupper portion of the digester being forced down into the lower portion,or highly heated zone, of the digester ready to have its treatment therecompleted by the. action of the heat by which the volatiles are morecompletely driven olf, and the tarry material rendered soft and incondition to hold the particles of solid matter to ether, so that whencommost highly heated point an the temperature of the upper zone aboutl600 degrees F. in its coolest portion.

After lthe mass has been thus expelled from the digester it should becut ov and the bottom 4 closed.

The plunger being withdrawn more coal is run into the digester until itislled and the plungrer is operated to compress the charge. he operationof heating until the coal is softened,l compressing, further heating andexpelling the lower portion of 4the charge is repeated, the operationbeing thus substantially continuous.

The operation has been described as conducted with a single digester butit is to be understood that two or more digesters are to be used.. Thesuperheated steam is discharged through -the perforations in pipes 28throughout the lower portion of the charge, aiding in equalizing theheat throughout the charge, and this steam finds its exit throughopenings 50 in the upper end of the digester and through pipe 40 to thedust collector 41 carrying with it the volatiles in the form of vapprsand gas and more or less solid matter which is eliminated by the dustcollector. l

The intervals of time between the compressing operations will dependsomewhat upon the temperature and the character of the raw material, butwill not be more than a few minutes. After each compression or operationof the iston it should be withdrawn to above t e inlet for the coal soas to permit free escape of volatiles and also to permit of suchexpansion or swelling of t e raw material as is likely to take place, asit is heated to the point of driving o the volatiles particularly withcoal such as cannel coal.

I do no herein claim the apparatus shown and described, as that formsthe subjectmatter of a separate application for patent for apparatus forcarbonizing coal, filed May 22, 1926, Serial Number 110,947.

Having thus described my invention what I claim iszln a process ofcarbonizin coal, heating comminuted coal to drive o moisture,introducing the coal in. heated condition into a digester closed at itsdischarge end and so heated by externally applied heat that the heat atits dischargel end is greater than at its inlet end, applying force tothe charge to compress it and to force it towards the discharge endofthe di ester and immediately withdrawing the orce ap lied, dischargingsuperheated steam into t e charge, subjecting the ,charge to the heat ofthc digester and of the superheated steam to drive y.off volatiles andto soften the coal in the more highly heated'portion of the digester, aain applying force to the charge to solidilgy the softened coal andimmediately withdrawing the force so applied, filling the spaceresulting from compressing the charge with heated coal, applying forceto the coal so introduced to compact it and to further solidify the coalin the more highly heated portion of the digester, subljecting thecharge to further action of the heat `of the digester and of thesuperheated steam, opening the discharge end of the digestor andapplying force to the char e to move the portion thereof last intro ucedfrom the less highly heated portion of the digester to the morehighlyheated portion and to expel the solidified mass contained in the morehighly heated portion.

In testimony whereof, I hereunto aiix my signature.

CHAS. HAYES.

